Radial Telescopic Transfer Arm
- Cost reduction: reduced size of the distribution chamber
- True UHV rotation
- Independent rotary motion
The new design will provide the ability to:
- Rotate an ‘Arm’ assembly to radial face ports about the chamber circumference.
- Drive the ‘Arm’ in and out of attached chambers (up to 700mm stroke).
- Lift and lower the ‘Arm’ to facilitate sample transfer.
The design includes specific features, not offered by the competition, with a view to providing next-generation performance, as now described.
True UHV rotation with no oil, slip rings, bellows or differential pumping The Radial Telescopic Transfer Arm will be actuated by the MD100 and MD35 MagiDrive rotary feedthroughs, providing true UHV performance, without any bellows, oil, slip rings or differential pumping. The larger MD100 has a break-away torque of ~40Nm, providing an extremely stiff coupling, ideal for rotating the 'Arm' assembly. The smaller MD35 actuates the mechanisms to drive the 'Arm' in and out.
Our design includes rotation of the 'Arm', extension of the 'Telescopic System' and lifting/lowering of the entire assembly to allow for 'gravity based' hand-off of the sample. This is the method typically employed on our MBE, sputtering and CVD sample manipulators/heating stages. However, should you not require the linear motion on the telescopic distribution manipulator and prefer to do the 'lifting' motion on each sample stage, then the price will reduce accordingly.
A key restraint on conventional RDC designs is the need for a large diameter chamber to house the rotating ‘Arm’ assembly. The internal diameter of the chamber is normally defined as the linear ‘Arm’ stroke required, plus the ‘distance between the bearings’ of the support system. UHV Design’s unique patented ‘Radial Telescopic Transfer Arm’ is very space efficient. The arm provides a sample position stroke of ~760mm. Fully withdrawn it will fit in a chamber with an internal diameter of 630mm, whilst holding a sample up to 138mm in diameter. If such a chamber were to have a port to centre line spacing of 359mm the reach from the flange would be 688mm The outcome of this design is that the customers’ chamber can be much smaller than with our competitors’ designs, saving cost on the chamber, pumps and frame. It also means that the overall footprint of the system would be considerably reduced.
An issue with many radial distribution chambers system designs is the issue of the rotating 'Arm' motion causing the 'Arm' extension assembly to move (often described as the axis cross-talk). Therefore, rotation of the 'Arm' also causes the sample to be driven in and out, losing its position. To overcome this, complex software programming is required to 'unwind' the secondary drive during rotation of the 'Arm'. UHV Design recognises this to be an unwanted feature and has, therefore, removed this as an issue through a unique mechanical design used on many other UHV Design manipulators over the years. In brief, this links the rotary motion of the MD100 'Arm' to the motor mounting of the smaller MD35, mechanically unwinding the undesired motion, without the need for complex software.
VACOM offers you a complete system consisting of transfer arm and vacuum distribution chamber. We are happy to help you with the design of your vacuum system and gladly provide you a free individual offer.